将7F双极心导管电极,从颈外静脉插入到上腔静脉与右心房连接处,记录到以P前波为特征的窦房结电图。它与兔的窦房结电图相似。P前波出现在相对应的心电图P波之前,窦房传导时间为16～37ms,舒张期斜坡之dv/dt为0.10～0.63mv/sec,向上斜坡之dv/dt为4.7～23.5mv/sec。波幅为100～600μv。P前波在刺激颈迷走神经或窦房结局部注入肾上腺素时发生改变,局部注入异搏定时消失,证实了P前波即窦房结电位。 The 7F bipolar cardiac catheter was inserted from the external jugular vein to the junction of the superior vena cava and the right atrium, and the sino-atrial node electrogram was recorded. It is similar to a rabbit’s sino-atrial electrogram. Before the P wave appeared in the corresponding P wave of electrocardiogram, the sinoatrial conduction time was 16-37 ms, the diastolic ramp dv / dt was 0.10-0.63 mv / sec, and the upward ramp dv / dt was 4.7-23.5 mv / sec . The amplitude is 100 ~ 600μv. P before the wave in the stimulation of cervical vagus nerve or sinus node injection of epinephrine changes when the local injection of verapamil timed disappear, confirmed that the P wave before the sinus node potential.